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-rw-r--r--arch/arm64/kernel/ptrace.c1913
1 files changed, 1913 insertions, 0 deletions
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
new file mode 100644
index 000000000..2817e3988
--- /dev/null
+++ b/arch/arm64/kernel/ptrace.c
@@ -0,0 +1,1913 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/kernel/ptrace.c
+ *
+ * By Ross Biro 1/23/92
+ * edited by Linus Torvalds
+ * ARM modifications Copyright (C) 2000 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/audit.h>
+#include <linux/compat.h>
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/task_stack.h>
+#include <linux/mm.h>
+#include <linux/nospec.h>
+#include <linux/smp.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/seccomp.h>
+#include <linux/security.h>
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/perf_event.h>
+#include <linux/hw_breakpoint.h>
+#include <linux/regset.h>
+#include <linux/tracehook.h>
+#include <linux/elf.h>
+
+#include <asm/compat.h>
+#include <asm/cpufeature.h>
+#include <asm/debug-monitors.h>
+#include <asm/fpsimd.h>
+#include <asm/mte.h>
+#include <asm/pointer_auth.h>
+#include <asm/stacktrace.h>
+#include <asm/syscall.h>
+#include <asm/traps.h>
+#include <asm/system_misc.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
+struct pt_regs_offset {
+ const char *name;
+ int offset;
+};
+
+#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
+#define REG_OFFSET_END {.name = NULL, .offset = 0}
+#define GPR_OFFSET_NAME(r) \
+ {.name = "x" #r, .offset = offsetof(struct pt_regs, regs[r])}
+
+static const struct pt_regs_offset regoffset_table[] = {
+ GPR_OFFSET_NAME(0),
+ GPR_OFFSET_NAME(1),
+ GPR_OFFSET_NAME(2),
+ GPR_OFFSET_NAME(3),
+ GPR_OFFSET_NAME(4),
+ GPR_OFFSET_NAME(5),
+ GPR_OFFSET_NAME(6),
+ GPR_OFFSET_NAME(7),
+ GPR_OFFSET_NAME(8),
+ GPR_OFFSET_NAME(9),
+ GPR_OFFSET_NAME(10),
+ GPR_OFFSET_NAME(11),
+ GPR_OFFSET_NAME(12),
+ GPR_OFFSET_NAME(13),
+ GPR_OFFSET_NAME(14),
+ GPR_OFFSET_NAME(15),
+ GPR_OFFSET_NAME(16),
+ GPR_OFFSET_NAME(17),
+ GPR_OFFSET_NAME(18),
+ GPR_OFFSET_NAME(19),
+ GPR_OFFSET_NAME(20),
+ GPR_OFFSET_NAME(21),
+ GPR_OFFSET_NAME(22),
+ GPR_OFFSET_NAME(23),
+ GPR_OFFSET_NAME(24),
+ GPR_OFFSET_NAME(25),
+ GPR_OFFSET_NAME(26),
+ GPR_OFFSET_NAME(27),
+ GPR_OFFSET_NAME(28),
+ GPR_OFFSET_NAME(29),
+ GPR_OFFSET_NAME(30),
+ {.name = "lr", .offset = offsetof(struct pt_regs, regs[30])},
+ REG_OFFSET_NAME(sp),
+ REG_OFFSET_NAME(pc),
+ REG_OFFSET_NAME(pstate),
+ REG_OFFSET_END,
+};
+
+/**
+ * regs_query_register_offset() - query register offset from its name
+ * @name: the name of a register
+ *
+ * regs_query_register_offset() returns the offset of a register in struct
+ * pt_regs from its name. If the name is invalid, this returns -EINVAL;
+ */
+int regs_query_register_offset(const char *name)
+{
+ const struct pt_regs_offset *roff;
+
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (!strcmp(roff->name, name))
+ return roff->offset;
+ return -EINVAL;
+}
+
+/**
+ * regs_within_kernel_stack() - check the address in the stack
+ * @regs: pt_regs which contains kernel stack pointer.
+ * @addr: address which is checked.
+ *
+ * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
+ * If @addr is within the kernel stack, it returns true. If not, returns false.
+ */
+static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
+{
+ return ((addr & ~(THREAD_SIZE - 1)) ==
+ (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))) ||
+ on_irq_stack(addr, NULL);
+}
+
+/**
+ * regs_get_kernel_stack_nth() - get Nth entry of the stack
+ * @regs: pt_regs which contains kernel stack pointer.
+ * @n: stack entry number.
+ *
+ * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
+ * is specified by @regs. If the @n th entry is NOT in the kernel stack,
+ * this returns 0.
+ */
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+ unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
+
+ addr += n;
+ if (regs_within_kernel_stack(regs, (unsigned long)addr))
+ return *addr;
+ else
+ return 0;
+}
+
+/*
+ * TODO: does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ /*
+ * This would be better off in core code, but PTRACE_DETACH has
+ * grown its fair share of arch-specific worts and changing it
+ * is likely to cause regressions on obscure architectures.
+ */
+ user_disable_single_step(child);
+}
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+/*
+ * Handle hitting a HW-breakpoint.
+ */
+static void ptrace_hbptriggered(struct perf_event *bp,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
+ const char *desc = "Hardware breakpoint trap (ptrace)";
+
+#ifdef CONFIG_COMPAT
+ if (is_compat_task()) {
+ int si_errno = 0;
+ int i;
+
+ for (i = 0; i < ARM_MAX_BRP; ++i) {
+ if (current->thread.debug.hbp_break[i] == bp) {
+ si_errno = (i << 1) + 1;
+ break;
+ }
+ }
+
+ for (i = 0; i < ARM_MAX_WRP; ++i) {
+ if (current->thread.debug.hbp_watch[i] == bp) {
+ si_errno = -((i << 1) + 1);
+ break;
+ }
+ }
+ arm64_force_sig_ptrace_errno_trap(si_errno,
+ (void __user *)bkpt->trigger,
+ desc);
+ }
+#endif
+ arm64_force_sig_fault(SIGTRAP, TRAP_HWBKPT,
+ (void __user *)(bkpt->trigger),
+ desc);
+}
+
+/*
+ * Unregister breakpoints from this task and reset the pointers in
+ * the thread_struct.
+ */
+void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
+{
+ int i;
+ struct thread_struct *t = &tsk->thread;
+
+ for (i = 0; i < ARM_MAX_BRP; i++) {
+ if (t->debug.hbp_break[i]) {
+ unregister_hw_breakpoint(t->debug.hbp_break[i]);
+ t->debug.hbp_break[i] = NULL;
+ }
+ }
+
+ for (i = 0; i < ARM_MAX_WRP; i++) {
+ if (t->debug.hbp_watch[i]) {
+ unregister_hw_breakpoint(t->debug.hbp_watch[i]);
+ t->debug.hbp_watch[i] = NULL;
+ }
+ }
+}
+
+void ptrace_hw_copy_thread(struct task_struct *tsk)
+{
+ memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
+}
+
+static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx)
+{
+ struct perf_event *bp = ERR_PTR(-EINVAL);
+
+ switch (note_type) {
+ case NT_ARM_HW_BREAK:
+ if (idx >= ARM_MAX_BRP)
+ goto out;
+ idx = array_index_nospec(idx, ARM_MAX_BRP);
+ bp = tsk->thread.debug.hbp_break[idx];
+ break;
+ case NT_ARM_HW_WATCH:
+ if (idx >= ARM_MAX_WRP)
+ goto out;
+ idx = array_index_nospec(idx, ARM_MAX_WRP);
+ bp = tsk->thread.debug.hbp_watch[idx];
+ break;
+ }
+
+out:
+ return bp;
+}
+
+static int ptrace_hbp_set_event(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx,
+ struct perf_event *bp)
+{
+ int err = -EINVAL;
+
+ switch (note_type) {
+ case NT_ARM_HW_BREAK:
+ if (idx >= ARM_MAX_BRP)
+ goto out;
+ idx = array_index_nospec(idx, ARM_MAX_BRP);
+ tsk->thread.debug.hbp_break[idx] = bp;
+ err = 0;
+ break;
+ case NT_ARM_HW_WATCH:
+ if (idx >= ARM_MAX_WRP)
+ goto out;
+ idx = array_index_nospec(idx, ARM_MAX_WRP);
+ tsk->thread.debug.hbp_watch[idx] = bp;
+ err = 0;
+ break;
+ }
+
+out:
+ return err;
+}
+
+static struct perf_event *ptrace_hbp_create(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx)
+{
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+ int err, type;
+
+ switch (note_type) {
+ case NT_ARM_HW_BREAK:
+ type = HW_BREAKPOINT_X;
+ break;
+ case NT_ARM_HW_WATCH:
+ type = HW_BREAKPOINT_RW;
+ break;
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+
+ ptrace_breakpoint_init(&attr);
+
+ /*
+ * Initialise fields to sane defaults
+ * (i.e. values that will pass validation).
+ */
+ attr.bp_addr = 0;
+ attr.bp_len = HW_BREAKPOINT_LEN_4;
+ attr.bp_type = type;
+ attr.disabled = 1;
+
+ bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk);
+ if (IS_ERR(bp))
+ return bp;
+
+ err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
+ if (err)
+ return ERR_PTR(err);
+
+ return bp;
+}
+
+static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
+ struct arch_hw_breakpoint_ctrl ctrl,
+ struct perf_event_attr *attr)
+{
+ int err, len, type, offset, disabled = !ctrl.enabled;
+
+ attr->disabled = disabled;
+ if (disabled)
+ return 0;
+
+ err = arch_bp_generic_fields(ctrl, &len, &type, &offset);
+ if (err)
+ return err;
+
+ switch (note_type) {
+ case NT_ARM_HW_BREAK:
+ if ((type & HW_BREAKPOINT_X) != type)
+ return -EINVAL;
+ break;
+ case NT_ARM_HW_WATCH:
+ if ((type & HW_BREAKPOINT_RW) != type)
+ return -EINVAL;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ attr->bp_len = len;
+ attr->bp_type = type;
+ attr->bp_addr += offset;
+
+ return 0;
+}
+
+static int ptrace_hbp_get_resource_info(unsigned int note_type, u32 *info)
+{
+ u8 num;
+ u32 reg = 0;
+
+ switch (note_type) {
+ case NT_ARM_HW_BREAK:
+ num = hw_breakpoint_slots(TYPE_INST);
+ break;
+ case NT_ARM_HW_WATCH:
+ num = hw_breakpoint_slots(TYPE_DATA);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ reg |= debug_monitors_arch();
+ reg <<= 8;
+ reg |= num;
+
+ *info = reg;
+ return 0;
+}
+
+static int ptrace_hbp_get_ctrl(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx,
+ u32 *ctrl)
+{
+ struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
+
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ *ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0;
+ return 0;
+}
+
+static int ptrace_hbp_get_addr(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx,
+ u64 *addr)
+{
+ struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
+
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ *addr = bp ? counter_arch_bp(bp)->address : 0;
+ return 0;
+}
+
+static struct perf_event *ptrace_hbp_get_initialised_bp(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx)
+{
+ struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
+
+ if (!bp)
+ bp = ptrace_hbp_create(note_type, tsk, idx);
+
+ return bp;
+}
+
+static int ptrace_hbp_set_ctrl(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx,
+ u32 uctrl)
+{
+ int err;
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+ struct arch_hw_breakpoint_ctrl ctrl;
+
+ bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
+ if (IS_ERR(bp)) {
+ err = PTR_ERR(bp);
+ return err;
+ }
+
+ attr = bp->attr;
+ decode_ctrl_reg(uctrl, &ctrl);
+ err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr);
+ if (err)
+ return err;
+
+ return modify_user_hw_breakpoint(bp, &attr);
+}
+
+static int ptrace_hbp_set_addr(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx,
+ u64 addr)
+{
+ int err;
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+
+ bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
+ if (IS_ERR(bp)) {
+ err = PTR_ERR(bp);
+ return err;
+ }
+
+ attr = bp->attr;
+ attr.bp_addr = addr;
+ err = modify_user_hw_breakpoint(bp, &attr);
+ return err;
+}
+
+#define PTRACE_HBP_ADDR_SZ sizeof(u64)
+#define PTRACE_HBP_CTRL_SZ sizeof(u32)
+#define PTRACE_HBP_PAD_SZ sizeof(u32)
+
+static int hw_break_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ unsigned int note_type = regset->core_note_type;
+ int ret, idx = 0;
+ u32 info, ctrl;
+ u64 addr;
+
+ /* Resource info */
+ ret = ptrace_hbp_get_resource_info(note_type, &info);
+ if (ret)
+ return ret;
+
+ membuf_write(&to, &info, sizeof(info));
+ membuf_zero(&to, sizeof(u32));
+ /* (address, ctrl) registers */
+ while (to.left) {
+ ret = ptrace_hbp_get_addr(note_type, target, idx, &addr);
+ if (ret)
+ return ret;
+ ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl);
+ if (ret)
+ return ret;
+ membuf_store(&to, addr);
+ membuf_store(&to, ctrl);
+ membuf_zero(&to, sizeof(u32));
+ idx++;
+ }
+ return 0;
+}
+
+static int hw_break_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ unsigned int note_type = regset->core_note_type;
+ int ret, idx = 0, offset, limit;
+ u32 ctrl;
+ u64 addr;
+
+ /* Resource info and pad */
+ offset = offsetof(struct user_hwdebug_state, dbg_regs);
+ ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
+ if (ret)
+ return ret;
+
+ /* (address, ctrl) registers */
+ limit = regset->n * regset->size;
+ while (count && offset < limit) {
+ if (count < PTRACE_HBP_ADDR_SZ)
+ return -EINVAL;
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
+ offset, offset + PTRACE_HBP_ADDR_SZ);
+ if (ret)
+ return ret;
+ ret = ptrace_hbp_set_addr(note_type, target, idx, addr);
+ if (ret)
+ return ret;
+ offset += PTRACE_HBP_ADDR_SZ;
+
+ if (!count)
+ break;
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl,
+ offset, offset + PTRACE_HBP_CTRL_SZ);
+ if (ret)
+ return ret;
+ ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl);
+ if (ret)
+ return ret;
+ offset += PTRACE_HBP_CTRL_SZ;
+
+ ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+ offset,
+ offset + PTRACE_HBP_PAD_SZ);
+ if (ret)
+ return ret;
+ offset += PTRACE_HBP_PAD_SZ;
+ idx++;
+ }
+
+ return 0;
+}
+#endif /* CONFIG_HAVE_HW_BREAKPOINT */
+
+static int gpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct user_pt_regs *uregs = &task_pt_regs(target)->user_regs;
+ return membuf_write(&to, uregs, sizeof(*uregs));
+}
+
+static int gpr_set(struct task_struct *target, const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct user_pt_regs newregs = task_pt_regs(target)->user_regs;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1);
+ if (ret)
+ return ret;
+
+ if (!valid_user_regs(&newregs, target))
+ return -EINVAL;
+
+ task_pt_regs(target)->user_regs = newregs;
+ return 0;
+}
+
+static int fpr_active(struct task_struct *target, const struct user_regset *regset)
+{
+ if (!system_supports_fpsimd())
+ return -ENODEV;
+ return regset->n;
+}
+
+/*
+ * TODO: update fp accessors for lazy context switching (sync/flush hwstate)
+ */
+static int __fpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct user_fpsimd_state *uregs;
+
+ sve_sync_to_fpsimd(target);
+
+ uregs = &target->thread.uw.fpsimd_state;
+
+ return membuf_write(&to, uregs, sizeof(*uregs));
+}
+
+static int fpr_get(struct task_struct *target, const struct user_regset *regset,
+ struct membuf to)
+{
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
+ if (target == current)
+ fpsimd_preserve_current_state();
+
+ return __fpr_get(target, regset, to);
+}
+
+static int __fpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf,
+ unsigned int start_pos)
+{
+ int ret;
+ struct user_fpsimd_state newstate;
+
+ /*
+ * Ensure target->thread.uw.fpsimd_state is up to date, so that a
+ * short copyin can't resurrect stale data.
+ */
+ sve_sync_to_fpsimd(target);
+
+ newstate = target->thread.uw.fpsimd_state;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate,
+ start_pos, start_pos + sizeof(newstate));
+ if (ret)
+ return ret;
+
+ target->thread.uw.fpsimd_state = newstate;
+
+ return ret;
+}
+
+static int fpr_set(struct task_struct *target, const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
+ ret = __fpr_set(target, regset, pos, count, kbuf, ubuf, 0);
+ if (ret)
+ return ret;
+
+ sve_sync_from_fpsimd_zeropad(target);
+ fpsimd_flush_task_state(target);
+
+ return ret;
+}
+
+static int tls_get(struct task_struct *target, const struct user_regset *regset,
+ struct membuf to)
+{
+ if (target == current)
+ tls_preserve_current_state();
+
+ return membuf_store(&to, target->thread.uw.tp_value);
+}
+
+static int tls_set(struct task_struct *target, const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ unsigned long tls = target->thread.uw.tp_value;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
+ if (ret)
+ return ret;
+
+ target->thread.uw.tp_value = tls;
+ return ret;
+}
+
+static int system_call_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ return membuf_store(&to, task_pt_regs(target)->syscallno);
+}
+
+static int system_call_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int syscallno = task_pt_regs(target)->syscallno;
+ int ret;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &syscallno, 0, -1);
+ if (ret)
+ return ret;
+
+ task_pt_regs(target)->syscallno = syscallno;
+ return ret;
+}
+
+#ifdef CONFIG_ARM64_SVE
+
+static void sve_init_header_from_task(struct user_sve_header *header,
+ struct task_struct *target)
+{
+ unsigned int vq;
+
+ memset(header, 0, sizeof(*header));
+
+ header->flags = test_tsk_thread_flag(target, TIF_SVE) ?
+ SVE_PT_REGS_SVE : SVE_PT_REGS_FPSIMD;
+ if (test_tsk_thread_flag(target, TIF_SVE_VL_INHERIT))
+ header->flags |= SVE_PT_VL_INHERIT;
+
+ header->vl = target->thread.sve_vl;
+ vq = sve_vq_from_vl(header->vl);
+
+ header->max_vl = sve_max_vl;
+ header->size = SVE_PT_SIZE(vq, header->flags);
+ header->max_size = SVE_PT_SIZE(sve_vq_from_vl(header->max_vl),
+ SVE_PT_REGS_SVE);
+}
+
+static unsigned int sve_size_from_header(struct user_sve_header const *header)
+{
+ return ALIGN(header->size, SVE_VQ_BYTES);
+}
+
+static int sve_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct user_sve_header header;
+ unsigned int vq;
+ unsigned long start, end;
+
+ if (!system_supports_sve())
+ return -EINVAL;
+
+ /* Header */
+ sve_init_header_from_task(&header, target);
+ vq = sve_vq_from_vl(header.vl);
+
+ membuf_write(&to, &header, sizeof(header));
+
+ if (target == current)
+ fpsimd_preserve_current_state();
+
+ /* Registers: FPSIMD-only case */
+
+ BUILD_BUG_ON(SVE_PT_FPSIMD_OFFSET != sizeof(header));
+ if ((header.flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD)
+ return __fpr_get(target, regset, to);
+
+ /* Otherwise: full SVE case */
+
+ BUILD_BUG_ON(SVE_PT_SVE_OFFSET != sizeof(header));
+ start = SVE_PT_SVE_OFFSET;
+ end = SVE_PT_SVE_FFR_OFFSET(vq) + SVE_PT_SVE_FFR_SIZE(vq);
+ membuf_write(&to, target->thread.sve_state, end - start);
+
+ start = end;
+ end = SVE_PT_SVE_FPSR_OFFSET(vq);
+ membuf_zero(&to, end - start);
+
+ /*
+ * Copy fpsr, and fpcr which must follow contiguously in
+ * struct fpsimd_state:
+ */
+ start = end;
+ end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
+ membuf_write(&to, &target->thread.uw.fpsimd_state.fpsr, end - start);
+
+ start = end;
+ end = sve_size_from_header(&header);
+ return membuf_zero(&to, end - start);
+}
+
+static int sve_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct user_sve_header header;
+ unsigned int vq;
+ unsigned long start, end;
+
+ if (!system_supports_sve())
+ return -EINVAL;
+
+ /* Header */
+ if (count < sizeof(header))
+ return -EINVAL;
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &header,
+ 0, sizeof(header));
+ if (ret)
+ goto out;
+
+ /*
+ * Apart from SVE_PT_REGS_MASK, all SVE_PT_* flags are consumed by
+ * sve_set_vector_length(), which will also validate them for us:
+ */
+ ret = sve_set_vector_length(target, header.vl,
+ ((unsigned long)header.flags & ~SVE_PT_REGS_MASK) << 16);
+ if (ret)
+ goto out;
+
+ /* Actual VL set may be less than the user asked for: */
+ vq = sve_vq_from_vl(target->thread.sve_vl);
+
+ /* Registers: FPSIMD-only case */
+
+ BUILD_BUG_ON(SVE_PT_FPSIMD_OFFSET != sizeof(header));
+ if ((header.flags & SVE_PT_REGS_MASK) == SVE_PT_REGS_FPSIMD) {
+ ret = __fpr_set(target, regset, pos, count, kbuf, ubuf,
+ SVE_PT_FPSIMD_OFFSET);
+ clear_tsk_thread_flag(target, TIF_SVE);
+ goto out;
+ }
+
+ /* Otherwise: full SVE case */
+
+ /*
+ * If setting a different VL from the requested VL and there is
+ * register data, the data layout will be wrong: don't even
+ * try to set the registers in this case.
+ */
+ if (count && vq != sve_vq_from_vl(header.vl)) {
+ ret = -EIO;
+ goto out;
+ }
+
+ sve_alloc(target);
+
+ /*
+ * Ensure target->thread.sve_state is up to date with target's
+ * FPSIMD regs, so that a short copyin leaves trailing registers
+ * unmodified.
+ */
+ fpsimd_sync_to_sve(target);
+ set_tsk_thread_flag(target, TIF_SVE);
+
+ BUILD_BUG_ON(SVE_PT_SVE_OFFSET != sizeof(header));
+ start = SVE_PT_SVE_OFFSET;
+ end = SVE_PT_SVE_FFR_OFFSET(vq) + SVE_PT_SVE_FFR_SIZE(vq);
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ target->thread.sve_state,
+ start, end);
+ if (ret)
+ goto out;
+
+ start = end;
+ end = SVE_PT_SVE_FPSR_OFFSET(vq);
+ ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+ start, end);
+ if (ret)
+ goto out;
+
+ /*
+ * Copy fpsr, and fpcr which must follow contiguously in
+ * struct fpsimd_state:
+ */
+ start = end;
+ end = SVE_PT_SVE_FPCR_OFFSET(vq) + SVE_PT_SVE_FPCR_SIZE;
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.uw.fpsimd_state.fpsr,
+ start, end);
+
+out:
+ fpsimd_flush_task_state(target);
+ return ret;
+}
+
+#endif /* CONFIG_ARM64_SVE */
+
+#ifdef CONFIG_ARM64_PTR_AUTH
+static int pac_mask_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ /*
+ * The PAC bits can differ across data and instruction pointers
+ * depending on TCR_EL1.TBID*, which we may make use of in future, so
+ * we expose separate masks.
+ */
+ unsigned long mask = ptrauth_user_pac_mask();
+ struct user_pac_mask uregs = {
+ .data_mask = mask,
+ .insn_mask = mask,
+ };
+
+ if (!system_supports_address_auth())
+ return -EINVAL;
+
+ return membuf_write(&to, &uregs, sizeof(uregs));
+}
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static __uint128_t pac_key_to_user(const struct ptrauth_key *key)
+{
+ return (__uint128_t)key->hi << 64 | key->lo;
+}
+
+static struct ptrauth_key pac_key_from_user(__uint128_t ukey)
+{
+ struct ptrauth_key key = {
+ .lo = (unsigned long)ukey,
+ .hi = (unsigned long)(ukey >> 64),
+ };
+
+ return key;
+}
+
+static void pac_address_keys_to_user(struct user_pac_address_keys *ukeys,
+ const struct ptrauth_keys_user *keys)
+{
+ ukeys->apiakey = pac_key_to_user(&keys->apia);
+ ukeys->apibkey = pac_key_to_user(&keys->apib);
+ ukeys->apdakey = pac_key_to_user(&keys->apda);
+ ukeys->apdbkey = pac_key_to_user(&keys->apdb);
+}
+
+static void pac_address_keys_from_user(struct ptrauth_keys_user *keys,
+ const struct user_pac_address_keys *ukeys)
+{
+ keys->apia = pac_key_from_user(ukeys->apiakey);
+ keys->apib = pac_key_from_user(ukeys->apibkey);
+ keys->apda = pac_key_from_user(ukeys->apdakey);
+ keys->apdb = pac_key_from_user(ukeys->apdbkey);
+}
+
+static int pac_address_keys_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct ptrauth_keys_user *keys = &target->thread.keys_user;
+ struct user_pac_address_keys user_keys;
+
+ if (!system_supports_address_auth())
+ return -EINVAL;
+
+ pac_address_keys_to_user(&user_keys, keys);
+
+ return membuf_write(&to, &user_keys, sizeof(user_keys));
+}
+
+static int pac_address_keys_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct ptrauth_keys_user *keys = &target->thread.keys_user;
+ struct user_pac_address_keys user_keys;
+ int ret;
+
+ if (!system_supports_address_auth())
+ return -EINVAL;
+
+ pac_address_keys_to_user(&user_keys, keys);
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &user_keys, 0, -1);
+ if (ret)
+ return ret;
+ pac_address_keys_from_user(keys, &user_keys);
+
+ return 0;
+}
+
+static void pac_generic_keys_to_user(struct user_pac_generic_keys *ukeys,
+ const struct ptrauth_keys_user *keys)
+{
+ ukeys->apgakey = pac_key_to_user(&keys->apga);
+}
+
+static void pac_generic_keys_from_user(struct ptrauth_keys_user *keys,
+ const struct user_pac_generic_keys *ukeys)
+{
+ keys->apga = pac_key_from_user(ukeys->apgakey);
+}
+
+static int pac_generic_keys_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct ptrauth_keys_user *keys = &target->thread.keys_user;
+ struct user_pac_generic_keys user_keys;
+
+ if (!system_supports_generic_auth())
+ return -EINVAL;
+
+ pac_generic_keys_to_user(&user_keys, keys);
+
+ return membuf_write(&to, &user_keys, sizeof(user_keys));
+}
+
+static int pac_generic_keys_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct ptrauth_keys_user *keys = &target->thread.keys_user;
+ struct user_pac_generic_keys user_keys;
+ int ret;
+
+ if (!system_supports_generic_auth())
+ return -EINVAL;
+
+ pac_generic_keys_to_user(&user_keys, keys);
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &user_keys, 0, -1);
+ if (ret)
+ return ret;
+ pac_generic_keys_from_user(keys, &user_keys);
+
+ return 0;
+}
+#endif /* CONFIG_CHECKPOINT_RESTORE */
+#endif /* CONFIG_ARM64_PTR_AUTH */
+
+#ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
+static int tagged_addr_ctrl_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ long ctrl = get_tagged_addr_ctrl(target);
+
+ if (IS_ERR_VALUE(ctrl))
+ return ctrl;
+
+ return membuf_write(&to, &ctrl, sizeof(ctrl));
+}
+
+static int tagged_addr_ctrl_set(struct task_struct *target, const struct
+ user_regset *regset, unsigned int pos,
+ unsigned int count, const void *kbuf, const
+ void __user *ubuf)
+{
+ int ret;
+ long ctrl;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, 0, -1);
+ if (ret)
+ return ret;
+
+ return set_tagged_addr_ctrl(target, ctrl);
+}
+#endif
+
+enum aarch64_regset {
+ REGSET_GPR,
+ REGSET_FPR,
+ REGSET_TLS,
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ REGSET_HW_BREAK,
+ REGSET_HW_WATCH,
+#endif
+ REGSET_SYSTEM_CALL,
+#ifdef CONFIG_ARM64_SVE
+ REGSET_SVE,
+#endif
+#ifdef CONFIG_ARM64_PTR_AUTH
+ REGSET_PAC_MASK,
+#ifdef CONFIG_CHECKPOINT_RESTORE
+ REGSET_PACA_KEYS,
+ REGSET_PACG_KEYS,
+#endif
+#endif
+#ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
+ REGSET_TAGGED_ADDR_CTRL,
+#endif
+};
+
+static const struct user_regset aarch64_regsets[] = {
+ [REGSET_GPR] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = sizeof(struct user_pt_regs) / sizeof(u64),
+ .size = sizeof(u64),
+ .align = sizeof(u64),
+ .regset_get = gpr_get,
+ .set = gpr_set
+ },
+ [REGSET_FPR] = {
+ .core_note_type = NT_PRFPREG,
+ .n = sizeof(struct user_fpsimd_state) / sizeof(u32),
+ /*
+ * We pretend we have 32-bit registers because the fpsr and
+ * fpcr are 32-bits wide.
+ */
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .active = fpr_active,
+ .regset_get = fpr_get,
+ .set = fpr_set
+ },
+ [REGSET_TLS] = {
+ .core_note_type = NT_ARM_TLS,
+ .n = 1,
+ .size = sizeof(void *),
+ .align = sizeof(void *),
+ .regset_get = tls_get,
+ .set = tls_set,
+ },
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ [REGSET_HW_BREAK] = {
+ .core_note_type = NT_ARM_HW_BREAK,
+ .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = hw_break_get,
+ .set = hw_break_set,
+ },
+ [REGSET_HW_WATCH] = {
+ .core_note_type = NT_ARM_HW_WATCH,
+ .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = hw_break_get,
+ .set = hw_break_set,
+ },
+#endif
+ [REGSET_SYSTEM_CALL] = {
+ .core_note_type = NT_ARM_SYSTEM_CALL,
+ .n = 1,
+ .size = sizeof(int),
+ .align = sizeof(int),
+ .regset_get = system_call_get,
+ .set = system_call_set,
+ },
+#ifdef CONFIG_ARM64_SVE
+ [REGSET_SVE] = { /* Scalable Vector Extension */
+ .core_note_type = NT_ARM_SVE,
+ .n = DIV_ROUND_UP(SVE_PT_SIZE(SVE_VQ_MAX, SVE_PT_REGS_SVE),
+ SVE_VQ_BYTES),
+ .size = SVE_VQ_BYTES,
+ .align = SVE_VQ_BYTES,
+ .regset_get = sve_get,
+ .set = sve_set,
+ },
+#endif
+#ifdef CONFIG_ARM64_PTR_AUTH
+ [REGSET_PAC_MASK] = {
+ .core_note_type = NT_ARM_PAC_MASK,
+ .n = sizeof(struct user_pac_mask) / sizeof(u64),
+ .size = sizeof(u64),
+ .align = sizeof(u64),
+ .regset_get = pac_mask_get,
+ /* this cannot be set dynamically */
+ },
+#ifdef CONFIG_CHECKPOINT_RESTORE
+ [REGSET_PACA_KEYS] = {
+ .core_note_type = NT_ARM_PACA_KEYS,
+ .n = sizeof(struct user_pac_address_keys) / sizeof(__uint128_t),
+ .size = sizeof(__uint128_t),
+ .align = sizeof(__uint128_t),
+ .regset_get = pac_address_keys_get,
+ .set = pac_address_keys_set,
+ },
+ [REGSET_PACG_KEYS] = {
+ .core_note_type = NT_ARM_PACG_KEYS,
+ .n = sizeof(struct user_pac_generic_keys) / sizeof(__uint128_t),
+ .size = sizeof(__uint128_t),
+ .align = sizeof(__uint128_t),
+ .regset_get = pac_generic_keys_get,
+ .set = pac_generic_keys_set,
+ },
+#endif
+#endif
+#ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
+ [REGSET_TAGGED_ADDR_CTRL] = {
+ .core_note_type = NT_ARM_TAGGED_ADDR_CTRL,
+ .n = 1,
+ .size = sizeof(long),
+ .align = sizeof(long),
+ .regset_get = tagged_addr_ctrl_get,
+ .set = tagged_addr_ctrl_set,
+ },
+#endif
+};
+
+static const struct user_regset_view user_aarch64_view = {
+ .name = "aarch64", .e_machine = EM_AARCH64,
+ .regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
+};
+
+#ifdef CONFIG_COMPAT
+enum compat_regset {
+ REGSET_COMPAT_GPR,
+ REGSET_COMPAT_VFP,
+};
+
+static inline compat_ulong_t compat_get_user_reg(struct task_struct *task, int idx)
+{
+ struct pt_regs *regs = task_pt_regs(task);
+
+ switch (idx) {
+ case 15:
+ return regs->pc;
+ case 16:
+ return pstate_to_compat_psr(regs->pstate);
+ case 17:
+ return regs->orig_x0;
+ default:
+ return regs->regs[idx];
+ }
+}
+
+static int compat_gpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ int i = 0;
+
+ while (to.left)
+ membuf_store(&to, compat_get_user_reg(target, i++));
+ return 0;
+}
+
+static int compat_gpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct pt_regs newregs;
+ int ret = 0;
+ unsigned int i, start, num_regs;
+
+ /* Calculate the number of AArch32 registers contained in count */
+ num_regs = count / regset->size;
+
+ /* Convert pos into an register number */
+ start = pos / regset->size;
+
+ if (start + num_regs > regset->n)
+ return -EIO;
+
+ newregs = *task_pt_regs(target);
+
+ for (i = 0; i < num_regs; ++i) {
+ unsigned int idx = start + i;
+ compat_ulong_t reg;
+
+ if (kbuf) {
+ memcpy(&reg, kbuf, sizeof(reg));
+ kbuf += sizeof(reg);
+ } else {
+ ret = copy_from_user(&reg, ubuf, sizeof(reg));
+ if (ret) {
+ ret = -EFAULT;
+ break;
+ }
+
+ ubuf += sizeof(reg);
+ }
+
+ switch (idx) {
+ case 15:
+ newregs.pc = reg;
+ break;
+ case 16:
+ reg = compat_psr_to_pstate(reg);
+ newregs.pstate = reg;
+ break;
+ case 17:
+ newregs.orig_x0 = reg;
+ break;
+ default:
+ newregs.regs[idx] = reg;
+ }
+
+ }
+
+ if (valid_user_regs(&newregs.user_regs, target))
+ *task_pt_regs(target) = newregs;
+ else
+ ret = -EINVAL;
+
+ return ret;
+}
+
+static int compat_vfp_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct user_fpsimd_state *uregs;
+ compat_ulong_t fpscr;
+
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
+ uregs = &target->thread.uw.fpsimd_state;
+
+ if (target == current)
+ fpsimd_preserve_current_state();
+
+ /*
+ * The VFP registers are packed into the fpsimd_state, so they all sit
+ * nicely together for us. We just need to create the fpscr separately.
+ */
+ membuf_write(&to, uregs, VFP_STATE_SIZE - sizeof(compat_ulong_t));
+ fpscr = (uregs->fpsr & VFP_FPSCR_STAT_MASK) |
+ (uregs->fpcr & VFP_FPSCR_CTRL_MASK);
+ return membuf_store(&to, fpscr);
+}
+
+static int compat_vfp_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct user_fpsimd_state *uregs;
+ compat_ulong_t fpscr;
+ int ret, vregs_end_pos;
+
+ if (!system_supports_fpsimd())
+ return -EINVAL;
+
+ uregs = &target->thread.uw.fpsimd_state;
+
+ vregs_end_pos = VFP_STATE_SIZE - sizeof(compat_ulong_t);
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
+ vregs_end_pos);
+
+ if (count && !ret) {
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpscr,
+ vregs_end_pos, VFP_STATE_SIZE);
+ if (!ret) {
+ uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
+ uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
+ }
+ }
+
+ fpsimd_flush_task_state(target);
+ return ret;
+}
+
+static int compat_tls_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ return membuf_store(&to, (compat_ulong_t)target->thread.uw.tp_value);
+}
+
+static int compat_tls_set(struct task_struct *target,
+ const struct user_regset *regset, unsigned int pos,
+ unsigned int count, const void *kbuf,
+ const void __user *ubuf)
+{
+ int ret;
+ compat_ulong_t tls = target->thread.uw.tp_value;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
+ if (ret)
+ return ret;
+
+ target->thread.uw.tp_value = tls;
+ return ret;
+}
+
+static const struct user_regset aarch32_regsets[] = {
+ [REGSET_COMPAT_GPR] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = COMPAT_ELF_NGREG,
+ .size = sizeof(compat_elf_greg_t),
+ .align = sizeof(compat_elf_greg_t),
+ .regset_get = compat_gpr_get,
+ .set = compat_gpr_set
+ },
+ [REGSET_COMPAT_VFP] = {
+ .core_note_type = NT_ARM_VFP,
+ .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
+ .size = sizeof(compat_ulong_t),
+ .align = sizeof(compat_ulong_t),
+ .active = fpr_active,
+ .regset_get = compat_vfp_get,
+ .set = compat_vfp_set
+ },
+};
+
+static const struct user_regset_view user_aarch32_view = {
+ .name = "aarch32", .e_machine = EM_ARM,
+ .regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
+};
+
+static const struct user_regset aarch32_ptrace_regsets[] = {
+ [REGSET_GPR] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = COMPAT_ELF_NGREG,
+ .size = sizeof(compat_elf_greg_t),
+ .align = sizeof(compat_elf_greg_t),
+ .regset_get = compat_gpr_get,
+ .set = compat_gpr_set
+ },
+ [REGSET_FPR] = {
+ .core_note_type = NT_ARM_VFP,
+ .n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
+ .size = sizeof(compat_ulong_t),
+ .align = sizeof(compat_ulong_t),
+ .regset_get = compat_vfp_get,
+ .set = compat_vfp_set
+ },
+ [REGSET_TLS] = {
+ .core_note_type = NT_ARM_TLS,
+ .n = 1,
+ .size = sizeof(compat_ulong_t),
+ .align = sizeof(compat_ulong_t),
+ .regset_get = compat_tls_get,
+ .set = compat_tls_set,
+ },
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ [REGSET_HW_BREAK] = {
+ .core_note_type = NT_ARM_HW_BREAK,
+ .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = hw_break_get,
+ .set = hw_break_set,
+ },
+ [REGSET_HW_WATCH] = {
+ .core_note_type = NT_ARM_HW_WATCH,
+ .n = sizeof(struct user_hwdebug_state) / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = hw_break_get,
+ .set = hw_break_set,
+ },
+#endif
+ [REGSET_SYSTEM_CALL] = {
+ .core_note_type = NT_ARM_SYSTEM_CALL,
+ .n = 1,
+ .size = sizeof(int),
+ .align = sizeof(int),
+ .regset_get = system_call_get,
+ .set = system_call_set,
+ },
+};
+
+static const struct user_regset_view user_aarch32_ptrace_view = {
+ .name = "aarch32", .e_machine = EM_ARM,
+ .regsets = aarch32_ptrace_regsets, .n = ARRAY_SIZE(aarch32_ptrace_regsets)
+};
+
+static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
+ compat_ulong_t __user *ret)
+{
+ compat_ulong_t tmp;
+
+ if (off & 3)
+ return -EIO;
+
+ if (off == COMPAT_PT_TEXT_ADDR)
+ tmp = tsk->mm->start_code;
+ else if (off == COMPAT_PT_DATA_ADDR)
+ tmp = tsk->mm->start_data;
+ else if (off == COMPAT_PT_TEXT_END_ADDR)
+ tmp = tsk->mm->end_code;
+ else if (off < sizeof(compat_elf_gregset_t))
+ tmp = compat_get_user_reg(tsk, off >> 2);
+ else if (off >= COMPAT_USER_SZ)
+ return -EIO;
+ else
+ tmp = 0;
+
+ return put_user(tmp, ret);
+}
+
+static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
+ compat_ulong_t val)
+{
+ struct pt_regs newregs = *task_pt_regs(tsk);
+ unsigned int idx = off / 4;
+
+ if (off & 3 || off >= COMPAT_USER_SZ)
+ return -EIO;
+
+ if (off >= sizeof(compat_elf_gregset_t))
+ return 0;
+
+ switch (idx) {
+ case 15:
+ newregs.pc = val;
+ break;
+ case 16:
+ newregs.pstate = compat_psr_to_pstate(val);
+ break;
+ case 17:
+ newregs.orig_x0 = val;
+ break;
+ default:
+ newregs.regs[idx] = val;
+ }
+
+ if (!valid_user_regs(&newregs.user_regs, tsk))
+ return -EINVAL;
+
+ *task_pt_regs(tsk) = newregs;
+ return 0;
+}
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+
+/*
+ * Convert a virtual register number into an index for a thread_info
+ * breakpoint array. Breakpoints are identified using positive numbers
+ * whilst watchpoints are negative. The registers are laid out as pairs
+ * of (address, control), each pair mapping to a unique hw_breakpoint struct.
+ * Register 0 is reserved for describing resource information.
+ */
+static int compat_ptrace_hbp_num_to_idx(compat_long_t num)
+{
+ return (abs(num) - 1) >> 1;
+}
+
+static int compat_ptrace_hbp_get_resource_info(u32 *kdata)
+{
+ u8 num_brps, num_wrps, debug_arch, wp_len;
+ u32 reg = 0;
+
+ num_brps = hw_breakpoint_slots(TYPE_INST);
+ num_wrps = hw_breakpoint_slots(TYPE_DATA);
+
+ debug_arch = debug_monitors_arch();
+ wp_len = 8;
+ reg |= debug_arch;
+ reg <<= 8;
+ reg |= wp_len;
+ reg <<= 8;
+ reg |= num_wrps;
+ reg <<= 8;
+ reg |= num_brps;
+
+ *kdata = reg;
+ return 0;
+}
+
+static int compat_ptrace_hbp_get(unsigned int note_type,
+ struct task_struct *tsk,
+ compat_long_t num,
+ u32 *kdata)
+{
+ u64 addr = 0;
+ u32 ctrl = 0;
+
+ int err, idx = compat_ptrace_hbp_num_to_idx(num);
+
+ if (num & 1) {
+ err = ptrace_hbp_get_addr(note_type, tsk, idx, &addr);
+ *kdata = (u32)addr;
+ } else {
+ err = ptrace_hbp_get_ctrl(note_type, tsk, idx, &ctrl);
+ *kdata = ctrl;
+ }
+
+ return err;
+}
+
+static int compat_ptrace_hbp_set(unsigned int note_type,
+ struct task_struct *tsk,
+ compat_long_t num,
+ u32 *kdata)
+{
+ u64 addr;
+ u32 ctrl;
+
+ int err, idx = compat_ptrace_hbp_num_to_idx(num);
+
+ if (num & 1) {
+ addr = *kdata;
+ err = ptrace_hbp_set_addr(note_type, tsk, idx, addr);
+ } else {
+ ctrl = *kdata;
+ err = ptrace_hbp_set_ctrl(note_type, tsk, idx, ctrl);
+ }
+
+ return err;
+}
+
+static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
+ compat_ulong_t __user *data)
+{
+ int ret;
+ u32 kdata;
+
+ /* Watchpoint */
+ if (num < 0) {
+ ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
+ /* Resource info */
+ } else if (num == 0) {
+ ret = compat_ptrace_hbp_get_resource_info(&kdata);
+ /* Breakpoint */
+ } else {
+ ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
+ }
+
+ if (!ret)
+ ret = put_user(kdata, data);
+
+ return ret;
+}
+
+static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
+ compat_ulong_t __user *data)
+{
+ int ret;
+ u32 kdata = 0;
+
+ if (num == 0)
+ return 0;
+
+ ret = get_user(kdata, data);
+ if (ret)
+ return ret;
+
+ if (num < 0)
+ ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
+ else
+ ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
+
+ return ret;
+}
+#endif /* CONFIG_HAVE_HW_BREAKPOINT */
+
+long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
+ compat_ulong_t caddr, compat_ulong_t cdata)
+{
+ unsigned long addr = caddr;
+ unsigned long data = cdata;
+ void __user *datap = compat_ptr(data);
+ int ret;
+
+ switch (request) {
+ case PTRACE_PEEKUSR:
+ ret = compat_ptrace_read_user(child, addr, datap);
+ break;
+
+ case PTRACE_POKEUSR:
+ ret = compat_ptrace_write_user(child, addr, data);
+ break;
+
+ case COMPAT_PTRACE_GETREGS:
+ ret = copy_regset_to_user(child,
+ &user_aarch32_view,
+ REGSET_COMPAT_GPR,
+ 0, sizeof(compat_elf_gregset_t),
+ datap);
+ break;
+
+ case COMPAT_PTRACE_SETREGS:
+ ret = copy_regset_from_user(child,
+ &user_aarch32_view,
+ REGSET_COMPAT_GPR,
+ 0, sizeof(compat_elf_gregset_t),
+ datap);
+ break;
+
+ case COMPAT_PTRACE_GET_THREAD_AREA:
+ ret = put_user((compat_ulong_t)child->thread.uw.tp_value,
+ (compat_ulong_t __user *)datap);
+ break;
+
+ case COMPAT_PTRACE_SET_SYSCALL:
+ task_pt_regs(child)->syscallno = data;
+ ret = 0;
+ break;
+
+ case COMPAT_PTRACE_GETVFPREGS:
+ ret = copy_regset_to_user(child,
+ &user_aarch32_view,
+ REGSET_COMPAT_VFP,
+ 0, VFP_STATE_SIZE,
+ datap);
+ break;
+
+ case COMPAT_PTRACE_SETVFPREGS:
+ ret = copy_regset_from_user(child,
+ &user_aarch32_view,
+ REGSET_COMPAT_VFP,
+ 0, VFP_STATE_SIZE,
+ datap);
+ break;
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ case COMPAT_PTRACE_GETHBPREGS:
+ ret = compat_ptrace_gethbpregs(child, addr, datap);
+ break;
+
+ case COMPAT_PTRACE_SETHBPREGS:
+ ret = compat_ptrace_sethbpregs(child, addr, datap);
+ break;
+#endif
+
+ default:
+ ret = compat_ptrace_request(child, request, addr,
+ data);
+ break;
+ }
+
+ return ret;
+}
+#endif /* CONFIG_COMPAT */
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+#ifdef CONFIG_COMPAT
+ /*
+ * Core dumping of 32-bit tasks or compat ptrace requests must use the
+ * user_aarch32_view compatible with arm32. Native ptrace requests on
+ * 32-bit children use an extended user_aarch32_ptrace_view to allow
+ * access to the TLS register.
+ */
+ if (is_compat_task())
+ return &user_aarch32_view;
+ else if (is_compat_thread(task_thread_info(task)))
+ return &user_aarch32_ptrace_view;
+#endif
+ return &user_aarch64_view;
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ switch (request) {
+ case PTRACE_PEEKMTETAGS:
+ case PTRACE_POKEMTETAGS:
+ return mte_ptrace_copy_tags(child, request, addr, data);
+ }
+
+ return ptrace_request(child, request, addr, data);
+}
+
+enum ptrace_syscall_dir {
+ PTRACE_SYSCALL_ENTER = 0,
+ PTRACE_SYSCALL_EXIT,
+};
+
+static void tracehook_report_syscall(struct pt_regs *regs,
+ enum ptrace_syscall_dir dir)
+{
+ int regno;
+ unsigned long saved_reg;
+
+ /*
+ * We have some ABI weirdness here in the way that we handle syscall
+ * exit stops because we indicate whether or not the stop has been
+ * signalled from syscall entry or syscall exit by clobbering a general
+ * purpose register (ip/r12 for AArch32, x7 for AArch64) in the tracee
+ * and restoring its old value after the stop. This means that:
+ *
+ * - Any writes by the tracer to this register during the stop are
+ * ignored/discarded.
+ *
+ * - The actual value of the register is not available during the stop,
+ * so the tracer cannot save it and restore it later.
+ *
+ * - Syscall stops behave differently to seccomp and pseudo-step traps
+ * (the latter do not nobble any registers).
+ */
+ regno = (is_compat_task() ? 12 : 7);
+ saved_reg = regs->regs[regno];
+ regs->regs[regno] = dir;
+
+ if (dir == PTRACE_SYSCALL_ENTER) {
+ if (tracehook_report_syscall_entry(regs))
+ forget_syscall(regs);
+ regs->regs[regno] = saved_reg;
+ } else if (!test_thread_flag(TIF_SINGLESTEP)) {
+ tracehook_report_syscall_exit(regs, 0);
+ regs->regs[regno] = saved_reg;
+ } else {
+ regs->regs[regno] = saved_reg;
+
+ /*
+ * Signal a pseudo-step exception since we are stepping but
+ * tracer modifications to the registers may have rewound the
+ * state machine.
+ */
+ tracehook_report_syscall_exit(regs, 1);
+ }
+}
+
+int syscall_trace_enter(struct pt_regs *regs)
+{
+ unsigned long flags = READ_ONCE(current_thread_info()->flags);
+
+ if (flags & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE)) {
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
+ if (flags & _TIF_SYSCALL_EMU)
+ return NO_SYSCALL;
+ }
+
+ /* Do the secure computing after ptrace; failures should be fast. */
+ if (secure_computing() == -1)
+ return NO_SYSCALL;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, regs->syscallno);
+
+ audit_syscall_entry(regs->syscallno, regs->orig_x0, regs->regs[1],
+ regs->regs[2], regs->regs[3]);
+
+ return regs->syscallno;
+}
+
+void syscall_trace_exit(struct pt_regs *regs)
+{
+ unsigned long flags = READ_ONCE(current_thread_info()->flags);
+
+ audit_syscall_exit(regs);
+
+ if (flags & _TIF_SYSCALL_TRACEPOINT)
+ trace_sys_exit(regs, syscall_get_return_value(current, regs));
+
+ if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
+
+ rseq_syscall(regs);
+}
+
+/*
+ * SPSR_ELx bits which are always architecturally RES0 per ARM DDI 0487D.a.
+ * We permit userspace to set SSBS (AArch64 bit 12, AArch32 bit 23) which is
+ * not described in ARM DDI 0487D.a.
+ * We treat PAN and UAO as RES0 bits, as they are meaningless at EL0, and may
+ * be allocated an EL0 meaning in future.
+ * Userspace cannot use these until they have an architectural meaning.
+ * Note that this follows the SPSR_ELx format, not the AArch32 PSR format.
+ * We also reserve IL for the kernel; SS is handled dynamically.
+ */
+#define SPSR_EL1_AARCH64_RES0_BITS \
+ (GENMASK_ULL(63, 32) | GENMASK_ULL(27, 26) | GENMASK_ULL(23, 22) | \
+ GENMASK_ULL(20, 13) | GENMASK_ULL(5, 5))
+#define SPSR_EL1_AARCH32_RES0_BITS \
+ (GENMASK_ULL(63, 32) | GENMASK_ULL(22, 22) | GENMASK_ULL(20, 20))
+
+static int valid_compat_regs(struct user_pt_regs *regs)
+{
+ regs->pstate &= ~SPSR_EL1_AARCH32_RES0_BITS;
+
+ if (!system_supports_mixed_endian_el0()) {
+ if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+ regs->pstate |= PSR_AA32_E_BIT;
+ else
+ regs->pstate &= ~PSR_AA32_E_BIT;
+ }
+
+ if (user_mode(regs) && (regs->pstate & PSR_MODE32_BIT) &&
+ (regs->pstate & PSR_AA32_A_BIT) == 0 &&
+ (regs->pstate & PSR_AA32_I_BIT) == 0 &&
+ (regs->pstate & PSR_AA32_F_BIT) == 0) {
+ return 1;
+ }
+
+ /*
+ * Force PSR to a valid 32-bit EL0t, preserving the same bits as
+ * arch/arm.
+ */
+ regs->pstate &= PSR_AA32_N_BIT | PSR_AA32_Z_BIT |
+ PSR_AA32_C_BIT | PSR_AA32_V_BIT |
+ PSR_AA32_Q_BIT | PSR_AA32_IT_MASK |
+ PSR_AA32_GE_MASK | PSR_AA32_E_BIT |
+ PSR_AA32_T_BIT;
+ regs->pstate |= PSR_MODE32_BIT;
+
+ return 0;
+}
+
+static int valid_native_regs(struct user_pt_regs *regs)
+{
+ regs->pstate &= ~SPSR_EL1_AARCH64_RES0_BITS;
+
+ if (user_mode(regs) && !(regs->pstate & PSR_MODE32_BIT) &&
+ (regs->pstate & PSR_D_BIT) == 0 &&
+ (regs->pstate & PSR_A_BIT) == 0 &&
+ (regs->pstate & PSR_I_BIT) == 0 &&
+ (regs->pstate & PSR_F_BIT) == 0) {
+ return 1;
+ }
+
+ /* Force PSR to a valid 64-bit EL0t */
+ regs->pstate &= PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT;
+
+ return 0;
+}
+
+/*
+ * Are the current registers suitable for user mode? (used to maintain
+ * security in signal handlers)
+ */
+int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task)
+{
+ /* https://lore.kernel.org/lkml/20191118131525.GA4180@willie-the-truck */
+ user_regs_reset_single_step(regs, task);
+
+ if (is_compat_thread(task_thread_info(task)))
+ return valid_compat_regs(regs);
+ else
+ return valid_native_regs(regs);
+}